1. AMO as the name suggests lets you place orders after market hours. You can place AMO on Zerodha Trader between 5:45 pm and 9:15 am for Equities and between 5:45 pm and 10:00 am for Commodities. After you’ve placed the order you can modify/cancel it. On market opening these orders would be sent to the Exchange. The AMO timings remain same for all market segment orders.

2. You don’t need a Demat account to carry forward Nifty Futures position. Only if you are trading for Intraday you get the benifit of trading with 40% of Exchange specified margins. To carry forward position you need to have the entire margins.. At current levels, margin required for 1 lot of Nifty is 24000 (overnight) and 9600 (40% of 24000 for intraday)